<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        li{
            width: 100px;
            height: 50px;
            background: blue;
            list-style: none;
            float: left;
            margin-right: 20px;
            margin-top: 10px;
            border-right: solid 3px red;
            padding-left: 20px;
        }
        ul{
            width: 450px;
        }
    </style>
</head>
<body>
<ul>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
    <li></li>
</ul>
</body>
</html>